Observation of coherence between the photoionization of different inner-shell vacancy states of argon and krypton

We have observed coherence between the photoionization of the 2s^-1{(}²S1/2) and the 2p^-1{(}²P3/2) inner-shell vacancy states of argon, and between the 3d^-1{(}²D3/2) and the 3d^-1{(}²D5/2) inner-shell vacancy states of krypton. The method is based on the occurrence of interferences between photoelectrons and Auger electrons, resulting from the photoionization and subsequent Auger decay of the two states concerned. A parametrization is proposed that describes the observed interference effects reasonably well.